Dynamics of cylindrical domain walls in nematic liquid crystals

TL;DR

This paper analytically investigates the dynamics of cylindrical domain walls in nematic liquid crystals under an external magnetic field, revealing decay behaviors of different wall types through polynomial expansion methods.

Contribution

It introduces an analytical approach to model the motion and decay of curved cylindrical domain walls in nematic liquid crystals, including the effects of external magnetic fields.

Findings

Neel walls decay faster than Bloch walls

Cylindrical domain walls shrink over time

Wall width changes during decay

Abstract

Analytical calculations of the dynamics of a curved domain wall in a nematic liquid crystal are performed. The core of the wall is assumed to form a cylinder, whose axis coincides with the direction of an external magnetic field. The equation of motion for the nematic director field is solved in a comoving coordinate frame by applying a polynomial expansion of the tilt angle with respect to the radial distance from the wall core. Starting from a cylindrical domain wall at rest as initial conditions, the shrinking of the cylinder and the change of the wall width is analysed in detail. In particular, we find that the Neel wall decays faster than the Bloch wall, in agreement with energy considerations.